diff --git a/xeofs/preprocessing/sanitizer.py b/xeofs/preprocessing/sanitizer.py
index 150b992..06f0765 100644
--- a/xeofs/preprocessing/sanitizer.py
+++ b/xeofs/preprocessing/sanitizer.py
@@ -102,7 +102,7 @@ def transform(self, X: DataArray) -> DataArray:
                 self.is_valid_feature,
                 X_valid_features,
                 X_valid_samples,
-                X_isolated_nan,
+                X_valid_features_per_sample,
             ) = dask.compute(
                 self.is_valid_feature,
                 X_valid_features,